Sounds like Moo Moo, correct spelling is Muumuu. It's a loose dress originating from Hawaii. Morbidly obese people typically wear muumuu's. It looks like they were made out of a flowery set of curtains.

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An extremely large person who could barely walk 10 feet without being winded and cannot see there own feet. Moomoos tend to be very defensive over their food and are not at all considerate of others. Moomoos tend to smell too.

I was stuck between 2 moomoos on my 9 hour flight. I couldnt stand the smell!!!!